Being underwater only matters if you want to sell or refinance. Hopefully, there's not many that bought in 2022 that are ready to sell. What will be an issue is over the next few years when those with a 6% rate or higher go to try and refinance their mortgage. Even if rates fall, they're going to get stuck at their higher rate because they don't have the equity. That's really where this is going to hurt.
Which doesn't help when there are a bunch of realtors telling people "buy now while rates are high and get a better deal on the purchase price, refi later"